Internal Redesign:

- Combined MPExpression and MPMutableExpression
- Abstracted children of MPExpression into MPExpressionElement protocol
- Abstracted most of MPExpressionLayout and MPFunctionLayout into common superclass MPLayout

MathPad/MPExpressionView.m

@@ -7,13 +7,15 @@
 //
 
 #import "MPExpressionView.h"
-#import "MPExpressionLayout.h"
 #import "MPExpressionStorage.h"
-
-#import "NSObject+MPStringTest.h"
+#import "MPExpressionLayout.h"
 
 #import "MPSumFunction.h"
 
+@interface MPExpressionView (MPCursor)
+@property (nonatomic, strong) NSTimer *cursorTimer;
+@end
+
 @implementation MPExpressionView
 
 #pragma mark Creation Methods
@@ -47,23 +49,20 @@
 
 - (void)initializeObjects
 {
-    MPExpressionStorage *expressionStorage = [[MPExpressionStorage alloc] initWithSymbols:@[@"12 345", [[MPSumFunction alloc] init], [[MPSumFunction alloc] init]]];
+    MPExpressionStorage *expressionStorage = [[MPExpressionStorage alloc] initWithElements:@[@"12345", [[MPSumFunction alloc] init], [[MPSumFunction alloc] init]]];
     _expressionStorage = expressionStorage;
-    [self.expressionLayout setExpressionView:self];
 }
 
 #pragma mark Properties
 
-- (void)setExpressionStorage:(MPExpressionStorage *)expressionStorage
+- (BOOL)isFlipped
 {
-    [_expressionStorage.expressionLayout setExpressionView:nil];
-    _expressionStorage = expressionStorage;
-    [_expressionStorage.expressionLayout setExpressionView:self];
+    return NO;
 }
 
-- (MPExpressionLayout *)expressionLayout
+- (void)setExpressionStorage:(MPExpressionStorage *)expressionStorage
 {
-    return self.expressionStorage.expressionLayout;
+    _expressionStorage = expressionStorage;
 }
 
 #pragma mark Drawing Methods
@@ -74,11 +73,10 @@
     [[NSColor whiteColor] set];
     NSRectFill(self.bounds);
     [[NSColor blackColor] set];
-    NSSize expressionSize = [self.expressionLayout sizeForAllSymbols];
+    NSSize expressionSize = [self.expressionStorage.rootLayout size];
     CGFloat y = (self.bounds.size.height - expressionSize.height) / 2;
-    NSLog(@"%f", self.bounds.origin.y);
     NSPoint point = NSMakePoint(self.bounds.origin.x, self.bounds.origin.y + y);
-    [self.expressionLayout drawAllSymbolsAtPoint:point];
+    [self.expressionStorage.rootLayout drawAtPoint:point];
 }
 
 @end